Special character in file name prevents transfer over SPICE webdav share

**Describe the issue**
Copying a folder over spice webdav share on a MacBook Pro m3 to a windows 11 ARM machine doesn't copy a file with a ? (filename?.txt). In this case no error is generated, which is preferable as without checking file counts you don't even know a file has been missed, wrongly assuming the copy was successful. It would be useful if the issue can't be resolved to warn of failures. To resolve the issue or workaround I can just remove the question mark to make it appear (to be clear it's not even visible on the share with a ? in)

**Configuration**
* UTM Version: 4.7.5 (115)
* macOS Version: Sequoia 15.5
* Mac Chip (Intel, M1, ...): M3 Pro

**Crash log**
No crash

**Debug log**
No crash, issue seems clear but let me know if you still need them as you can't reproduce.